Bug: Nix hashes for nodes_modules incorrectly generated

[jerome-benoit]

Description

error: hash mismatch in fixed-output derivation '/nix/store/xnfhz6wwaxsvjkya5qlvprr9897xh7hg-opencode-node_modules-1.1.25.drv':
         specified: sha256-07XxcHLuToM4QfWVyaPLACxjPZ93ZM7gtpX2o08Lp18=
            got:    sha256-aNdV977azPcVVT8oyJWeurlELYejhafinNclRq9gsj0=

It looks like a race condition in the CI caused by a recent refactoring: the file is written by a step for a platform while another concurrent one is also doing it. At the end, only one change is taken and the hashes are not properly updated for all platforms.

The original implementation was sequential and duplicated a lot of code on purpose to avoid that kind of race condition. Using matrix can be done once you are SURE that each step wait for the end of the previous one before starting or that the hashes file content is put in a shared memory that can be read/write by all steps, and dumped once all steps are done in the file if a concurrent approach is used.

Plugins

No response

OpenCode version

No response

Steps to reproduce

No response

Screenshot and/or share link

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Operating System

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Terminal

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[github-actions]

While investigating this issue, I found several related Nix-related issues that may provide useful context:

• When built from the flake, opencode package is extremely large (4GB+) #4853: Package size bloat (4GB+) due to all platform binaries being bundled
• Desktop build on nixos #8962: Desktop build issues on NixOS with IPC requests
• desktop - missing desktop application entry on nix #8971: Missing desktop application entry on NixOS
• [Bug] Nix error when using ! in opencode #6468: Nix error when using ! in opencode
• NixOS: custom tools fail because they cannot find imported modules #5914: NixOS custom tools fail due to missing imported modules

These issues address different aspects of Nix integration. This issue (#8977) specifically focuses on CI hash generation race conditions. If this fix affects the other issues, please update accordingly.

[rekram1-node]

Yeah i think I need someone more in nix to be reviewing every pr I merge seems to fix it for someone and break it for another

[rekram1-node]

Some new nix prs:
#8964
#8972

[jerome-benoit]

Yeah i think I need someone more in nix to be reviewing every pr I merge seems to fix it for someone and break it for another

To fix the current issue with hashes quickly, a job for each platform must be implemented, each one using needs: <previous one>; it's ugly and introduce duplication but works (or use a matrix lock action, but I do not the real gain here). Then investigate how to use a shared memory between a step and a matrix to handle concurrent runs.